Not being from a construction background at all, so probably a silly question but would a new site (if it ever did happen) have to be flattish ? if not there's loads of land either side of Midhurst Road over the back of the training ground and across the Don.

There was talk a while ago of a stadium move to an area on Weedon Street near Meadowhall, this story puts the kybosh on that as the area is looking at being turned into an industrial estate by the company that owns Meadowhall https://www.thestar.co.uk/news/picture-nearly-5000-jobs-could-be-created-at-new-industrial-complex-near-sheffield-s-meadowhall-1-9332327

Think redevelopment is the way forward, someone mocked up one a while ago that extended over Penistone Road and made a tunnel for the road that was quite jazzy !! Incorporate that in with the world cup plans.

There was a lot of cutlery factories around there my granddad worked at Hirum Wilds which was next to the old bus garage so it might have been something similar I can still remember the steel being polished smell now about 35 years later